The Rickenbacker 4003 is part of Rickenbacker's 4000 series of bass guitars. The 4003 has been in production since 1979. With its unusual shape and beautiful tone, The Rickenbacker 4003 Bass is the ideal instrument for any serious musician. The 4003 is an updated verison of the 4001 series. It was given different truss rods, and no skunk-stripe.